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排序方式: 共有2028条查询结果,搜索用时 15 毫秒
61.
Gulen Melike Demirbolat Levent Altintas Sukran Yilmaz Ismail Tuncer Degim 《Journal of pharmaceutical sciences》2018,107(5):1398-1407
Nanoparticulate systems have been receiving a significant attention especially for the treatment of cancer but one of the main hurdles is to produce these developed and high-tech nanosystems in large quantities. Anticancer drug formulations are generally designed for parenteral administrations but oral administration is still the most convenient route. In this study, orally applicable nano-sized chitosan nanoparticles (NPs) were successfully prepared using Nano Spray Dryer. It is possible to produce these NPs in large quantities by simply increasing the processing time using the machine without changing any parameter. A chemotherapeutic agent (imatinib mesylate; IMA) and nonsteroidal anti-inflammatory drug (dexketoprofen trometamol) were loaded together in these NPs. NPs were also functionalized with polyethylene glycol and folic acid to obtain long circulating NPs and tumor targeting. The antitumoral activities of formulations showed that these developed NPs can enhance the effectiveness. Animal experiments were performed on fibrosarcoma-bearing mice model, and the treatment with 0.8 mg/μL/kg IMA-loaded chitosan NPs was found to be successful to slow down the growth of tumors. The tumor tissues were removed from the animals and enzymatic activities were evaluated. The inhibitory effect of tyrosine kinase was found to be enhanced from 36.4% to 68.4% when IMA was used in combination with dexketoprofen trometamol. Furthermore, all dried NPs were found to be stable for more than a year at 25°C. Presented results show that these developed combinatorial drug–loaded NPs can be used for the treatment of fibrosarcoma, and these data can provide an insight, new strategies for productions or alternatives in cancer treatment. 相似文献
62.
Psoriatic arthritis is an autoimmune, chronic, systemic inflammatory disorder characterized by the association of arthritis
with psoriasis. In this paper, we explore the characteristics of joint and nail involvement in Turkish patients with psoriatic
arthritis. Forty patients with psoriasis (M/F, 18/22) and 49 (M/F, 25/24) subjects with psoriatic arthritis were included
in the study. Clinical characteristics of the patients were recorded. The distribution of the subjects with arthritis: (according
to the clinical and radiological findings): polyarticular, 65%; oligoarticular, 23%; isolated axial involvement, 7.7%; arthritis
mutilans, 3.8%; sacroiliitis, 19%. Nail involvement was significantly higher among patients with arthritis; i.e., 91 versus
32%; (P < 0.05). There were no correlation between the skin involvement pattern and the arthritis type (P > 0.05). Nevertheless, no relation was observed between the psoriasis duration and arthritis (P > 0.05). Nail involvement is a frequent feature of the psoriatic arthritis which may be a useful finding for differential
diagnosis of psoriatic arthritis from other inflammatory arthropathies. 相似文献
63.
Coronary artery aneurysms are defined as coronary dilatations which exceed the diameter of normal adjacent segments by 1.5 times. Left main coronary artery (LMCA) is the least frequently involved artery with a prevalence of 0.1%. Majority of coronary artery aneurysms are atherosclerotic in origin. Their size and clinical presentation is variable. A number of complications have been reported to occur during the course of the disease including thrombosis and distal embolization, myocardial ischemia and/or infarction, dissection, vasospasm, calcification, fistulization and very rarely rupture. Large aneurysms of LMCA represent a potentially fatal condition even without concomitant atherosclerotic coronary disease. Because of rarity of coronary artery aneurysms, it is difficult to standardize treatment. In this article, we presented 4 cases of large LMCA aneurysms with various clinical and angiographic features. 相似文献
64.
Possible benefits of vitamin K on bone health, fracture risk, markers of bone formation and resorption, cardiovascular health, and cancer risk in postmenopausal women have been investigated for over three decades; yet there is no clear evidence-based universal recommendation for its use. 相似文献
65.
66.
Introduction
The aim of this study was to compare the effect of the EndoVac irrigation system (SybronEndo, Orange, CA) and conventional endodontic needle irrigation on sealer penetration into dentinal tubules.Methods
Forty single-rooted, recently extracted human maxillary central incisors were randomly divided into 2 groups according to the irrigation technique used: conventional endodontic needle irrigation and EndoVac irrigation. All teeth were instrumented using the ProFile rotary system (Dentsply Maillefer, Ballaigues, Switzerland) and obturated with gutta-percha and AH Plus sealer (Dentsply DeTrey, Konstanz, Germany) labeled with fluorescent dye. Transverse sections at 1, 3, and 5 mm from the root apex were examined using confocal laser scanning microscopy. The total percentage and maximum depth of sealer penetration were then measured.Results
Mann-Whitney test results showed that EndoVac irrigation resulted in a significantly higher percentage of sealer penetration than conventional irrigation at both the 1- and 3-mm levels (P < .05). However, no difference was found at the 5-mm level. The 5-mm sections in each group showed a significantly higher percentage and maximum depth of sealer penetration than did the 1- and 3-mm sections (P < .05).Conclusions
The EndoVac irrigation system significantly improved the sealer penetration at the 1- to 3-mm level over that of conventional endodontic needle irrigation. 相似文献67.
Merve Banko?lu Güng?r Handan Y?lmaz Cemal Ayd?n Se?il Karakoca Nemli Bilge Turhan Bal Tülay T?ra? 《The journal of advanced prosthodontics》2014,6(3):224-232
PURPOSE
The purpose of the present study was to evaluate the effect of thermocycling and mechanical loading on the biaxial flexural strength and the phase transformation of one Ce-TZP/Al2O3 and two Y-TZP core materials.MATERIALS AND METHODS
Thirty disc-shaped specimens were obtained from each material. The specimens were randomly divided into three groups (control, thermocycled, and mechanically loaded). Thermocycling was subjected in distilled water for 10000 cycles. Mechanical loading was subjected with 200 N loads at a frequency of 2 Hz for 100000 times. The mean biaxial flexural strength and phase transformation of the specimens were tested. The Weibull modulus, characteristic strength, 10%, 5% and 1% probabilities of failure were calculated using the biaxial flexural strength data.RESULTS
The characteristic strengths of Ce-TZP/Al2O3 specimens were significantly higher in all groups compared with the other tested materials (P<.001). Statistical results of X-ray diffraction showed that thermocycling and mechanical loading did not affect the monoclinic phase content of the materials. According to Raman spectroscopy results, at the same point and the same material, mechanical loading significantly affected the phase fraction of all materials (P<.05).CONCLUSION
It was concluded that thermocycling and mechanical loading did not show negative effect on the mean biaxial strength of the tested materials. 相似文献68.
Aydin F Güngör F Cengiz AK Tuncer M Mahsereci E Ozdem S Cenkçi M Karayalçin B 《Nuclear medicine communications》2008,29(2):157-165
OBJECTIVE: To compare measured glomerular filtration rate (GFR) by single plasma sample methods (SPSMs), gamma camera Gates, 24-h endogenous creatinine clearance, and prediction equations (Cockcroft-Gault and modification of renal disease (MDRD)) with the two plasma sample method (TPSM) considered as the reference in potential kidney donors with normal renal function. METHODS: One hundred and fifteen subjects (50 male, 65 female; mean age 41.9+/-12.2 years) with normal renal function were prospectively included in this study. GFR was calculated by TPSM (120-min and 240-min samples) and SPSM (180-min sample). RESULTS: While there was strong statistically significant correlation between the TPSM and all SPSMs, low correlation was found in Gates, creatinine clearance, Cockcroft-Gault and MDRD. In all SPSMs, 95% limits of agreements were consistent with each other and within clinically acceptable limits. The lowest bias, median absolute difference, mean percentage error, and the best precision were found for Christensen and Groth's method as modified by Watson (CGmW). CONCLUSIONS: Among the SPSMs, CGmW can reflect GFR more accurately than the other methods. Neither the gamma camera Gates method nor the creatinine clearance method nor the prediction equations (Cockcroft-Gault and MDRD) could calculate GFR accurately. All these techniques could result in mistakes in the management of potential kidney donors. 相似文献
69.
Vatansev C Belviranli M Aksoy F Tuncer S Sahin M Karahan O 《Surgical laparoscopy, endoscopy & percutaneous techniques》2002,12(4):243-246
Although tension-free techniques of hernia repair using synthetic meshes have yielded encouraging results, the best method of inguinal hernia repair is still unclear. The aim of this study was to compare the responses of inflammatory mediators and postoperative pain relief following laparoscopic total extraperitoneal (TEP) hernioplasty, open tension-free mesh hernioplasty (Lichtenstein), posterior preperitoneal mesh hernioplasty (Nyhus procedure), and Bassini procedure. Patients with primary inguinal hernia were randomized in the operating room to undergo one of these repair techniques. Group I comprised 24 patients treated by Lichtenstein procedure; Group II comprised 21 patients treated by Nyhus procedure; Group III comprised 19 patients treated by Bassini procedure; and Group IV comprised 20 patients treated by laparoscopic TEP mesh hernioplasty. Postoperative pain levels following hernia repair were compared by measuring the use of patient-controlled analgesia (PCA) during the 24 hours after surgery. Serum samples withdrawn before surgery and 48 hours after surgery were assayed for C-reactive protein (CRP) content. Patient characteristics, operating time, and operative and early complications were noted. Serum CRP levels rose markedly following Nyhus (184.5 +/- 41.6 mg/L), Lichtenstein (138.4 +/- 72.5 mg/L), and Bassini repair (137.2 +/- 55.9 mg/L) compared with that of patients who underwent TEP mesh hernioplasty (55.5 +/- 41.2 mg/L). There were also significant differences in the postoperative need for analgesics via PCA among patients undergoing Nyhus (382.9 +/- 189.1 mg), Bassini (303.2 +/- 173.7 mg), and Lichtenstein (253.9 +/- 129.3) procedures compared with 196.6 +/- 148.8 mg for the TEP mesh hernioplasty group. Patients in the Lichtenstein group also had significantly less need of analgesics than those in the Nyhus and Bassini groups. In conclusion, TEP mesh hernioplasty is less traumatic and yields less postoperative pain than the Nyhus, Lichtenstein, and Bassini procedures. 相似文献
70.
Antioxidative effects of cysteamine,hyaluronan and fetuin on post‐thaw semen quality,DNA integrity and oxidative stress parameters in the Brown Swiss bull 下载免费PDF全文
S. Sarıözkan P. B. Tuncer S. Büyükleblebici M. N. Bucak F. Cantürk A. Eken 《Andrologia》2015,47(2):138-147
The aim of this study was to compare the effectiveness of antioxidants including cysteamine (2.5, 7.5 mm ), hyaluronan (0.25, 1 mg ml?1) and fetuin (5, 10 mg ml?1) in the freezing of Brown Swiss bull semen. The best percentages of CASA motilities were achieved with 10 mg ml?1 of fetuin and 2.5 mm of cysteamine. For sperm morphology, 10 mg ml?1 of fetuin and 2.5 mm of cysteamine had better protective effects (P < 0.001). The results of hypo‐osmotic swelling test showed that the percentage values of membrane integrity in all the groups, excluding that supplemented with 5 mg ml?1 of fetuin, were higher than those of the control group (P < 0.001). Results obtained for the DNA damage of sperm cells demonstrated that 0.25 mg ml?1 of hyaluronan, and 2.5 and 7.5 mm of cysteamine led to lower rates of spermatozoa with damaged DNA, compared with the control group (P < 0.001). The maintenance of superoxide dismutase and glutathione peroxidase antioxidant activities following freeze‐thawing with 2.5 and 7.5 mm of cysteamine and 10 mg ml?1 of fetuin was demonstrated to be at a higher level in comparison with the control group (P < 0.001). Malondialdehyde formation was found to be lower in the groups supplemented with 0.25 mg ml?1 of hyaluronan and 7.5 mm of cysteamine after the freeze‐thawing process (P < 0.001). 相似文献